<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

    <!--开发版本-->
    <link rel="stylesheet" href="static/plugins/bootstrap-3.4.1/css/bootstrap.css">

    <!--生产版本-->
    <link rel="stylesheet" href="static/plugins/bootstrap-3.4.1/css/bootstrap.min.css">

</head>
<body>
    <input type="button" value="提交">
    <input type="button" value="提交" class="btn btn-link">
    <input type="button" value="提交" class="btn btn-group">
    <input type="button" value="提交" class="btn btn-success">


</body>
</html>